This invention is directed generally to bearing assemblies, and more particularly to roller bearings having an improved bearing seal and cartridge.
Bearing assemblies often include various components including rolling elements that are retained within the assembly to reduce friction and wear between moving parts or surfaces. A typical bearing assembly includes an inner ring that rotates relative to an outer ring of the bearing during operation and the rolling elements are positioned between the inner and outer rings. The bearing assemblies contain a lubricant that serves to protect the rolling elements from contact with either the inner or outer races of the bearing during operation. It is desirable to provide a sealing arrangement between the inner the inner and outer rings of the bearing to retain the lubricant within the bearing assembly. Such sealing arrangements are often referred to as a bearing seal cartridge. In many applications, the bearing assemblies are used in applications where the bearings are exposed to harsh operating environments where contaminants such as grit and dust are present. The sealing arrangement also serves to prevent any contaminants from entering the area where the rolling elements are positioned. Prior sealing arrangements suffer from any number of disadvantages, including complex constructions that are difficult to manufacture and costly to make and replace, providing too much or too little drag during rotation, or providing insufficient lubricant retention or contaminant exclusion. Thus, there is a need to provide a sealing arrangement, or bearing seal cartridge, that is relatively simple in construction, yet provides sufficient sealing, acceptable drag rotational drag, and sufficient lubricant retention and contaminant exclusion.
The present embodiment is specifically directed to a bearing assembly having a bearing inner ring with an inner raceway and a bearing outer ring with an outer raceway and a plurality of rolling elements positioned therebetween. The present embodiment further includes a seal carrier fixed with respect to the outer ring having a flange extending generally radially inward toward the bearing inner ring. There is also a flinger element fixed with respect to the bearing inner ring that includes a first flange having an inner surface facing the outer ring and a second flange extending from the first flange in a radial direction and inwardly angled in a direction toward the outer raceway of the outer ring. Thus, the second flange is angled so as to provide a tapered inner surface. A flexible sealing member is affixed to an end of the seal carrier and has a first sealing leg contacting the inner surface of the first flange of the flinger element, a second sealing leg also contacting the inner surface of the first flange of the flinger element, and a third sealing leg contacting the tapered inner surface of the second flange of the flinger element. The distance between the flange of the seal carrier and the tapered inner surface of the second flange may be adjustable to provide more or less rotational drag as desired.
The present embodiment allows for a larger chamber area for lubricant, or grease, to be maintained between the second and third sealing legs of the flexible sealing member. In addition, the tapered second flange of the flinger element allows for a shorter, thinner axial lip on the third sealing leg, yet still provides an appropriate sealing force. This allows for a more economical overall design of the flexible sealing member. There is also more space for the radial lip design, while simultaneously reducing the gap between the flinger and the seal carrier. Thus, creating a narrower area for contaminants to enter the bearing assembly. Furthermore, the tapered second flange of the flinger helps to force contaminants up along the flinger, to provide a better flinging action.
The foregoing and other objects, features and advantages of the bearing seal cartridge will be apparent from the following more particular description of preferred embodiments as illustrated in the accompanying drawings.